foo.cc: In function 'int main()':
foo.cc:24:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   24 |  scanf("%d%d", &n,&m);
      |  ~~~~~^~~~~~~~~~~~~~~
foo.cc:27:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   27 |   scanf("%d", &a[i]);
      |   ~~~~~^~~~~~~~~~~~~

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